Method of and system for training in firing guided missiles from a mobile platform

ABSTRACT

In a method of and device for training in firing guided missiles from a mobile platform, both a device for generating a spot simulating a trace of the missile, and the eyepiece of an aiming device, are made unitary with said platform, an image of the real landscape is gyroscopically stabilized in relation to the platform, and an image of the spot simulating a trace of the missile is superimposed on the landscape image by introducing the spot image into the eyepiece of the aiming device.

United States Patent Inventors Georges Colin Essonne; Pierre de Guillenchmidt, Hauts-de-Seine, both of France Appl. No. 783,889 Filed Dec. 16, 1968 Patented Dec. 28, 1971 Assignee Giravions Dorand Suresnes, France Priority Feb. 16, 1968 France 140097 METHOD OF AND SYSTEM FOR TRAINING IN FIRING GUIDED MISSILES FROM A MOBILE PLATFORM 9 Claims, 3 Drawing Figs.

US. Cl 35/25 Int. Cl F4lg 3/26, G09b 9/00 Field of Search 35/25;

[56] References Cited UNITED STATES PATENTS 3,406,402 10/1968 Stautfet a1 343/225 3,446,980 5/1969 Meier 350/16 X 3,507,055 4/1970 Claunch et al 35/25 FOREIGN PATENTS 1,489,865 7/1967 France 35/25 Primary Examiner-Robert W. Michell Assistant Examiner-L. R. Oremland Attorney-Holman & Stern ABSTRACT: In a method of and device for training in firing guided missiles from a mobile platform, both a device for generating a spot simulating a trace of the missile, and the eyepiece of an aiming device, are made unitary with said platform, an image of the real landscape is gyroscopically stabilized in relation to the platform, and an image of the spot simu lating a trace of the missile is superimposed on the landscape image by introducing the spot image into the eyepiece of the aiming device.

PATENTED M82 1 SHEET 1 [IF 3 PATENTEU DEC28 1971 SHEET 2 [IF 3 PATENTEU DEC28197I SHEET 3 OF 3 FIG?) METHOD OF AND SYSTEM FOR TRAINING IN FIRING GUIDED MISSILES FROM A MOBILE PLATFORM The present invention relates to a new method of training in firing guided missiles, by an observer situated on a mobile platform in front of a real landscape, and observing, through an aiming device normally used for firing, the image of a spot simulating a trace of the missile, superimposed on the stable image of this landscape.

The invention also relates to a device for use in carrying out the aforesaid method as well as apparatus for training in firing guided missiles, with optical simulation of a trace of the missile, and adapted for use on mobile platforms such for example as aircraft, helicopters, ships, and tanks and other land vehicles.

The method and device according to the invention allow the firing of imaginary missiles from mobile platforms by means of the same aiming and firing apparatus and in the same aiming conditions and surroundings as are involved in the firing of real missiles.

For training in firing missiles from fixed platforms, firing simulators are already known such as that marketed by the Company GIRAVIONS DORAND under the trade name Exosimulator DX-43, allowing simulated shots at real targets, fixed or mobile.

These simulators generally comprise: an optical system based on the principle of the light chamber and comprising a semireflecting or semitransparent mirror and a generator of a light spot simulating a trace of the missile, arranged in such a way that the target to be hit in a real landscape and the spot simulating a trace of the missile can be observed simultaneously by the firer, the first by transparency through the mirror and the second by reflection on the mirror; an aiming device allowing this observation; a guiding device or firing handle allowing the firer to control, through the intermediary of the computer, the positional changes of the spot in the same way as he would control the positional changes of a real missile; a computer controlling, with the help of a set of servomechanisms, the angular displacements of a mirror in order to simulate the ordered movements of the imaginary missile whose trace is represented by the light spot, as a function on the one hand of predetennined initial conditions (such as speed of the missile and duration of its flight), and, on the other hand, of the orders of the firer transmitted by the guiding device.

In such simulators, usable only for firing from fixed platforms, the fact that the optical observation system is itself fixed justifies the arrangement, in front of the pupil under instruction, of an optical enlarging device which allows observation and firing at long range.

Devices of the foregoing type cannot be directly used for training in firing from a mobile platform, since, in this latter case, the spot simulating a trace of the missile must be made independent of the movements of the said platform.

To this end, there had already been proposed:

either to introduce gyroscopically stabilized mirrors into the spots optical system;

or to have recourse to the signals of a control gyroscope in dependent of the optical pack and to introduce, by means of the simulators computer, correcting orders to the guided mirror.

Both of these arrangements considerably complicate the structure of the simulator, and increase its price.

In addition, neither of these arrangements allows the presence of an enlarging optical system (which would considerably facilitate long-range firing) at the entry to the optical pack as the unstabilized image of the landscape is subject to the movements of the platform and leaves the limited field of vision of the enlarging system on every movement, however small, of the platform.

In order to allow use of an enlarging system, and to avoid the foregoing disadvantages, it has already been proposed to make the entire optical pack an integral part of the stabilized aiming device, such as binoculars, with which it is associated.

This device results in an increase in the weight of the assembly to be gyroscopically stabilized, entailing considerable increase in the bulk and cost of the simulator.

The primary object of the present invention is to overcome the disadvantages of the devices hereinbefore described.

The present invention is a method of providing an observer situated on a mobile platform with the image of a spot simulating a trace of the missile and superimposed on the stable image of a real landscape in an aiming device, said method comprising the steps of gyroscopically stabilizing the image of the real landscape in relation to the mobile platform, introducing into the eyepiece of the aiming device the guided image of said spot, and making the spot-generating device and the eyepiece of the aiming device integral with said platform.

The present invention is also a device for training in firing guided missiles from a mobile platform, said device comprising an aiming device integral with said mobile platform and comprising an optical device assembled as an episcope, a gyroscopically stabilized overhead mirror, an eyepiece, a plane semireflecting mirror adapted to receive from said overhead mirror the stabilized image of a real landscape and send it back towards said eyepiece, an optical device for generating a light spot which simulates a trace of the missile and is subordinate to a guiding mechanism for said spot which directs the guided spot towards said eyepiece through said semireflecting mirror.

The aiming device of the device according to the invention is preferably the gyrostabilized aimer sold by the Company BEZU under the trade name APX-BEZU M 260, which comprises an overhead mirror arranged as an episcope and mechanically linked to a gyroscopic system. In such an aiming device the landscape image is integral with the system of axes of the device.

The light spot is advantageously guided by a positionally variable mirror mechanically subordinate to a piloting servomechanism commanded by a computer to which is linked a firing handle maneuvered by the firer.

The light spot can be emitted by the light-source-forming real image of the filament of an electric light bulb, said image being formed by the light rays of the said bulb in a small glass sphere situated in front of the filament of the bulb.

According to one advantageous embodiment of the device according to the invention, the small glass sphere is contained in a conical bore passing through a fixed oblique mirror situated opposite the positionally variable mirror, and sending back towards the eyepiece the spot reflected by the positionally variable mirror.

The aiming device advantageously comprises on the one hand a plane reticular lens situated just in front of the eyepiece, and, on the other hand, a device for reerecting the image of the real landscape. This reerecting device, according to the characteristics of the aiming device, can be mounted either between the semireflecting mirror and the plane reticular lens or between the overhead mirror and the semireflecting mirror.

The optical pack may comprise, in front of the semireflecting mirror, either a lens focused on the light spot formed in the small glass sphere, or a lens projecting said light spot on to the plane reticular lens.

In the first case, a second lens, focused on the plane reticular lens, is advantageously arranged either between the first lens and the semireflecting mirror, or behind the latter.

A device according to the invention for training in firing guided missiles is shown, by way of example, in the accompanying diagrammatic drawings, in which FIGS. 1 to 3 are incomplete functional views of three embodiments of said device.

In the device in FIG. 1, the light rays emitted by an electric light bulb with a filament l, forming the source of light for the optical pack 2 of the device, pass through a small glass sphere 3 placed in front of the filament l of the bulb, which gives a real image of the rays, almost a pinpoint. This image in turn plays the part of a light source and the spot or ray which it emits strikes a guided plane mirror 4, on which it is reflected. The spot is then sent back in the direction of a fixed oblique mirror 5 which in turn deviates it towards a lens 6 situated on the rear face of the optical pack 2. The two mirrors 4, S are arranged so that the real image of the light source is to be found at the focal point of the lens 6, which provides a virtual image thereof situated at infinity. This virtual image is introduced into the eyepiece 7 of an aiming device with the aid of an optical arrangement comprising a semireflecting mirror 8, acting in parallel with a lens 9 of the aiming device and allowing superimposition of the images of the landscape transmitted to the lens 9 by an overhead mirror 10 of the aiming device, and of the light spot, at the level of the focal plane of the eyepiece 7.

The overhead mirror 10 is mechanically linked to a gyroscopic system which is part of a stabilizer pack indicated at 11, and which comprises, besides, a servomechanism.

The image of the light spot is made mobile by means of the guided plane mirror 4. This mirror 4 is fixed on a support, held in a yoke 12 integral with a horizontal shaft linked to a controlling servomechanism in the direction of the spot. Mounted on a bearing, the support of mirror 4 is movable, within the yoke 12, around an axis perpendicular to the axis of the aforesaid horizontal shaft and is free to turn around this perpendicular axis, through the agency of a countershaft supported by ball-and-socket joints and linked to a depth servomechanism. Such as arrangement allows the combination of the two degrees of freedom of mirror 4.

The two servomechanisms, denoted at 13 in the form of a control box, operate as commanded and are controlled by signals issued by a computer (not shown) in which are worked out the simulated missiles flight conditions, in space and time, taking account on the one hand of conditions stated initially (especially initial speed and position of the missile and the duration of flight of the latter) and, on the other hand, of orders issued from a handle (not shown) maneuvered by the observer/firer.

The movements of the light spot simulating the missile being likewise worked out in relation to the system of axes of the viewfinder, everything takes place as if these movements were being carried out from a firing platform connected to the ground.

Such as arrangement allows calculation without the necessity of taking account of the angular movements of the platform. Accepting, however, that a movement in its bearings of the overhead mirror 10 of the viewfinder results in an inclination of the image of the landscape, corresponding to a rotation of its rolling axes, the computer includes a servomechanism, controlled by the inclination movement, which effects the necessary change of coordinates.

In addition to the arrangements described, the device of FIGv 1 also comprises, on the one hand, between the lens 6, focused on the light spot, and the semireflecting mirror 8, a second lens 14 focused on a plane reticular lens 15 situated just in front of the eyepiece 7 and, on the other hand between the said semireflecting mirror 8 and the plane reticular lens 15, a reerecting device 16 for the image.

In FIG. 2, the elements of the device shown, identical or similar to those of the device in FIG. I, are indicated by the same reference numbers as before. The device of FIG. 2 is in fact distinguishable from that in FIG. I only by the replacement of lenses 9 and 14 (FIG. 1) by a single lens 17 (FIG. 2) situated between the semireflecting or semitransparent mirror 8 and the reerecting device I6 for the image.

In FIG. 3, the elements of the device shown, identical or similar to those shown in FIG. 1, have the same reference numbers as before.

In the device in FIG. 3, the mirror 5 of the device of FIGS. 1 and 2 is omitted thanks to the positioning of the filament l of the lamp and the small glass sphere 3, below the guided mirror 4, the mounting of the latter being similar to that of the overhead mirror 10 of the aiming device, and the axis of the yoke 12 being vertical.

A single lens 18 is arranged between the guided mirror 4 and the semitransparent mirror, this lens projecting the light spot formed in the sphere 3 on to the plane reticular lens 15.

On the other hand, an objective 19 and two lenses 20, 2] constituting a reerecting device for the image, are arranged between the overhead mirror 10 and the semitransparent mirror 8.

Naturally, the invention is in no way limited to the examples described and illustrated; it is capable of numerous variations within the field of the specialist according to the applications envisaged without departing from the scope of the inventionv We claim:

I. A method of providing an observer situated on a mobile platform with the image of a spot simulating a trace of a guided missile and superimposed on the. stable image of a real landscape in an aiming device, said method comprising the steps of gyroscopically stabilizing the image of the real landscape in relation to the mobile platform, introducing into the eyepiece of the aiming device the guided image of said spot, and making the spot-generating device and the eyepiece of the aiming device integral with said platform.

2. A system for training in firing a guided missile from a mobile platform and guiding the fired missile towards a target, comprising an aiming device mounted on said mobile platform and comprising an optical enlarging device assembled as an episcope and including a gyroscopically stabilized overhead mirror, an eyepiece, a plane semitransparent mirror adapted to receive from said overhead mirror the stabilized image of a real landscape and reflect such stabilized image towards said eyepiece, a source of light, a projecting device capable of superimposing on said stabilized image, by projection on said semitransparent mirror, a beam of light forming an image of the source of light, said latter image representing said guided missile, said projecting device including a mirror mounted for pivotal movement about two perpendicular axes whereby to shift said missile-representing image in azimuth and elevation, respectively, and a guiding device operatively connected with said pivotable mirror and controllable by the firer for correcting deviations of the missile-representing image relative to the line of sight.

3. A system according to claim 2, further comprising a piloting servomechanism operatively connected to said pivotal mirror of said projecting device and controllable by a computer to which is connected a firing handle maneuvered by the firer.

4. A system according to claim 2, in which the light beam emitted by said source of light is projected onto said pivotable mirror through a small glass ball.

5. A system according to claim 4 in which said small glass ball is disposed between said source of light and said pivotable mirror of the projecting device, and in which said projecting device further includes a lens disposed in the optical axis between said pivotable mirror and the semitransparent mirror, said lens being focused on the light spot within said glass ball and on the reticular lens of the optical enlarging device.

6. A system according to claim 4 wherein the beam projected onto said pivotable mirror is reflected by the latter towards a fixed mirror located above the pivotable mirror and forming an angle of 45 with the reflected beam so as to deflect the same through the semitransparent mirror of the optical enlarging device towards said eyepiece thereof, said small glass ball being disposed in a conical aperture formed in said fixed mirror.

7. A system according to claim 6, in which said projecting device further includes two lenses disposed in the optical axis between said fixed mirror and the semitransparent mirror of the optical enlarging device, one of said lenses being focused on the light spot formed on said glass ball, and the other lens being focused on the reticular lens of the optical enlarging device.

8. A system according to claim 6 in which said projecting device further includes a lens disposed in the optical axis between said pivotable mirror and the semitransparent mirror,

larging device further includes optical means interposed between said semitransparent means and said eyepiece for reerecting said image of a real landscape, and a plane reticular lens disposed between said eyepiece and said optical means. 

1. A method of providing an observer situated on a mobile platform with the image of a spot simulating a trace of a guided missile and superimposed on the stable image of a real landscape in an aiming device, said method comprising the steps of gyroscopically stabilizing the image of the real landscape in relation to the mobile platform, introducing into the eyepiece of the aiming device the guided image of said spot, and making the spot-generating device and the eyepiece of the aiming device integral with said platform.
 2. A system for training in firing a guided missile from a mobile platform and guiding the fired missile towards a target, comprising an aiming device mounted on said mobile platform and comprising an optical enlarging device assembled as an episcope and including a gyroscopically stabilized overhead mirror, an eyepiece, a plane semitransparent mirror adapted to receive from said overhead mirror the stabilized image of a real landscape and reflect such stabilized image towards said eyepiece, a source of light, a projecting device capable of superimposing on said stabilized image, by projection on said semitransparent mirror, a beam of light forming an image of the source of light, said latter image representing said guided missile, said projecting device including a mirror mounted for pivotal movement about two perpendicular axes whereby to shift said missile-representing image in azimuth and elevation, respectively, and a guiding device operatively connected with said pivotable mirror and controllable by the firer for correcting deviations of the missile-representing image relative to the line of sight.
 3. A system according to claim 2, further comprising a piloting servomechanism operatively connected to said pivotal mirror of said projecting device and controllable by a computer to which is connected a firing handle manouvered by the firer.
 4. A system according to claim 2, in which the light beam emitted by said source of Light is projected onto said pivotable mirror through a small glass ball.
 5. A system according to claim 4 in which said small glass ball is disposed between said source of light and said pivotable mirror of the projecting device, and in which said projecting device further includes a lens disposed in the optical axis between said pivotable mirror and the semitransparent mirror, said lens being focused on the light spot within said glass ball and on the reticular lens of the optical enlarging device.
 6. A system according to claim 4 wherein the beam projected onto said pivotable mirror is reflected by the latter towards a fixed mirror located above the pivotable mirror and forming an angle of 45* with the reflected beam so as to deflect the same through the semitransparent mirror of the optical enlarging device towards said eyepiece thereof, said small glass ball being disposed in a conical aperture formed in said fixed mirror.
 7. A system according to claim 6, in which said projecting device further includes two lenses disposed in the optical axis between said fixed mirror and the semitransparent mirror of the optical enlarging device, one of said lenses being focused on the light spot formed on said glass ball, and the other lens being focused on the reticular lens of the optical enlarging device.
 8. A system according to claim 6 in which said projecting device further includes a lens disposed in the optical axis between said pivotable mirror and the semitransparent mirror, said lens being focused on the light spot within said glass ball, and in which the optical enlarging device further includes a lens positioned in the optical axis between said reticular lens and said semitransparent mirror and focused on said reticular lens.
 9. A system according to claim 2, in which said optical enlarging device further includes optical means interposed between said semitransparent means and said eyepiece for reerecting said image of a real landscape, and a plane reticular lens disposed between said eyepiece and said optical means. 